In the first part of World War II, the Red Army fielded weaponry of mixed quality. It had excellent artillery, but it did not have enough trucks to maneuver and supply it; as a result the Wehrmacht (which rated it highly) captured much of it. Red Army T-34 tanks generally outclassed other tanks until 1943, yet most of the Soviet armored units were less advanced models; likewise, the same supply problem handicapped even the formations equipped with the most modern tanks. The Soviet Air Force initially performed poorly against the Germans. The quick advance of the Germans into the Soviet territory made reinforcement and replacements much more difficult since much of the Soviet Union's military industry lay in the west of the country. Until the Soviet authorities re-established the industry east of the Urals, much improvisation was necessary, and Soviet units were routinely far below their weapons establishment levels.